Mud Fever – the new thinking on treatments

  • In this weeks Horse and Hound (20.12.12) the Veterinary article was on Mud Fever. For those of you that do not know, Mud Fever is a condition that normally infects horses who live out in fields. When the horses get a cut on their leg and it is not properly cleaned and dressed, however small it may be, there is a large chance that it will be infected with Mud Fever the next time the horse goes in the field.

So what’s the standard treating of Mud Fever? – Horses’ legs must be washed with COLD water, as warm water would open up the pores and make them more susceptible. If any cuts are found they must be scrubbed with ‘hibiscrub’, all scabs picked off, and then must have sudocream applied. If for any reason the horse has a particularly deep/big cut it must be bandaged and the horse box rested for an applicable amount of time. If properly treated like this, mud fever will not infect your horse.

Why is Mud Fever on the increase? – The recent weather ( constant rain!) as disrupted the typical day of many horses and has provided many irritants that cause inflamed and infected skin. The technical name for Mud Fever being ‘pastern dermatitis’ is actually a range of skin reactions to a number of different irritants. Mud Fever is triggered by cold, wet and muddy conditions, leading for Mud Fever to largely strike in winter months.

Why can it be so hard to treat in some conditions? – New vet research shoes ‘antimicrobial resistance’ to be the real problem. A recent study from the University of Liverpool investigated the prescribing of antimicrobials in UK vet equine practices; looking at how vets treated severe cases of pastern dermatitis: 80% used antimicrobials. Less than 1% of vets worked in practices with written antimicrobial usage guidelines which encourage more careful prescribing. 61% of vets reported they rarely or never weigh a horse when they are prescribing medication.

In my opinion, these results are particularly interesting. Throughout my one week work experience at a small vet practice, every animal was weighed, even if it was just being checked over. So why would horses be any different? Without weighing them vets are likely to give the horses an inappropriate dosage. So why take the risk? Is it just laziness of not wanting to weigh a large animal? Or not having the facilities to weigh one? Furthermore, it is quite shocking to see that less than 1% actually have usage guidelines on how to actually prescribe this medication!

Spotting Mud Fever – Mud fever usually happen’s on the horse’s leg, where there is an open, untreated wound. In more sever cases, it is usually found at the back of the pastern and around the heel area, where crusty scabs will start to appear. Discharge from the sore skin can cause hair to clump or even fall out. In some cases, the skin at the back of the leg can split open , leading to deep horizontal cracks. It is easy for bacteria to enter through this damaged skin, resulting in hot,swollen and painful legs, severe lameness and the need for intensive therapy.

However, non -bacterial causes are also common. They include fungal infection and infestation of tiny mites cause ‘chorioptic mange’, which are similar to those that might cause scabies in humans. These mites are particularly common in horses with feathers (very hairy legs).

In addition, pastern inflammation can also be triggered by a disorder of the body’s immune system that attacks the skin, known as ‘leukocyroclastic vasculitis’. It targets unpigmented areas of the lower limbs. It is a problem in both summer and winter, and no amount of creams, lotions or antibiotics will control it.

My conclusion on the use of Antimicrobials – neither mites, fungal infections nor leukocytoclastic vasculitis respond to antimicrobials, which is one of the many reasons why they are not a cure- all for lower limb irritations. Furthermore, I found the investigation of the students in the University of Liverpool very interesting. I know for certain if my own horse has to be treated for severe mud fever I will be particularly insistent that my horse be weighed and the prescription of antimicrobials comes with useful guidelines. However, this applies in all aspects of Veterinary, how do we know our animals are being treated efficiently and correctly? For me, analysing and looking at this article has been a real eye opener, in the future I will more readily question the treatment of my horse for any problem she might have.

If you are interested in further exploring Mud Fever and seeing what it looks like, simply type it in on the Google Search Bar!

I hope you have enjoyed reading this article, more to come soon 🙂